Get 20M+ Full-Text Papers For Less Than $1.50/day. Start a 14-Day Trial for You or Your Team.

Learn More →

Characterization of a thermostable dihydrodipicolinate synthase from Thermoanaerobacter tengcongensis

Characterization of a thermostable dihydrodipicolinate synthase from Thermoanaerobacter... Dihydrodipicolinate synthase (DHDPS) catalyses the first reaction of the (S)-lysine biosynthesis pathway in bacteria and plants. The hypothetical gene for dihydrodipicolinate synthase (dapA) of Thermoanaerobacter tengcongensis was found in a cluster containing several genes of the diaminopimelate lysine–synthesis pathway. The dapA gene was cloned in Escherichia coli, DHDPS was subsequently produced and purified to homogeneity. The T. tengcongensis DHDPS was found to be thermostable (T 0.5 = 3 h at 90°C). The specific condensation of pyruvate and (S)-aspartate-β -semialdehyde was catalyzed optimally at 80°C at pH 8.0. Enzyme kinetics were determined at 60°C, as close as possible to in vivo conditions. The established kinetic parameters were in the same range as for example E. coli dihydrodipicolinate synthase. The specific activity of the T. tengcongensis DHDPS was relatively high even at 30°C. Like most dihydrodipicolinate synthases known at present, the DHDPS of T. tengcongensis seems to be a tetramer. A structural model reveals that the active site is well conserved. The binding site of the allosteric inhibitor lysine appears not to be conserved, which agrees with the fact that the DHDPS of T. tengcongensis is not inhibited by lysine under physiological conditions. http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png Extremophiles Springer Journals

Characterization of a thermostable dihydrodipicolinate synthase from Thermoanaerobacter tengcongensis

Loading next page...
 
/lp/springer-journals/characterization-of-a-thermostable-dihydrodipicolinate-synthase-from-c20cRv7sY9

References (42)

Publisher
Springer Journals
Copyright
Copyright © 2008 by Springer
Subject
Life Sciences; Ecology; Biotechnology; Microbiology
ISSN
1431-0651
eISSN
1433-4909
DOI
10.1007/s00792-008-0152-z
pmid
18340401
Publisher site
See Article on Publisher Site

Abstract

Dihydrodipicolinate synthase (DHDPS) catalyses the first reaction of the (S)-lysine biosynthesis pathway in bacteria and plants. The hypothetical gene for dihydrodipicolinate synthase (dapA) of Thermoanaerobacter tengcongensis was found in a cluster containing several genes of the diaminopimelate lysine–synthesis pathway. The dapA gene was cloned in Escherichia coli, DHDPS was subsequently produced and purified to homogeneity. The T. tengcongensis DHDPS was found to be thermostable (T 0.5 = 3 h at 90°C). The specific condensation of pyruvate and (S)-aspartate-β -semialdehyde was catalyzed optimally at 80°C at pH 8.0. Enzyme kinetics were determined at 60°C, as close as possible to in vivo conditions. The established kinetic parameters were in the same range as for example E. coli dihydrodipicolinate synthase. The specific activity of the T. tengcongensis DHDPS was relatively high even at 30°C. Like most dihydrodipicolinate synthases known at present, the DHDPS of T. tengcongensis seems to be a tetramer. A structural model reveals that the active site is well conserved. The binding site of the allosteric inhibitor lysine appears not to be conserved, which agrees with the fact that the DHDPS of T. tengcongensis is not inhibited by lysine under physiological conditions.

Journal

ExtremophilesSpringer Journals

Published: Mar 15, 2008

There are no references for this article.